Machine for generating multisided apertures



Nov.- 25, 1941. H. J. SCHRODE R MACHINE FOR GENERATING MUL'IISIDEDAPERTURES Filed Sept. 5, 1958 5 Sheets-Sheet l H. J. SCHRCSDER Nov. 25,1941.

- MACHINE FOR GENERATING MULTIICSIDED APERTURES Filed Sept. 3, 1938 5Sheets-Sheet 2 1941- H. J. SCHRODER MACHINE FOR GENERATING MULTISIDEDAPERTURES- 5 Sheets-Sheet 5 Filed Sept. 3, 1938 Fig. 5

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MACHINE FOR GENERATING MULTISIDED APERTURES Filed Sept. 5., 1938 sSheets-Sheet 4 Nov. 25, 1941. H. J. scHRODER MACHINE FOR GENERATINGMULTISIDED APERTURES 5 Sheets-Sheet 5 Filed Sept. 3, 1938 I Inventor:660.: 7a'acfiz'm Sammie 4 with the aid of th 'accompanying Patented Nov.2 5a1941 I TED; STATES PATENT. Z series MACHINE For:

GENERATING MU 'rrsmEn anemones Hans Joachim Schriider. Dessam Germany,as-

signor, to

Junkers Flugleugmnd Motoren- Aktimsesellschflt, Des'sau, Germany," aration of Germany Application September-3,1938, sens! naafzaso'z.

. In Germany September 6, 1937 z This invention relates a machine forgenerating multi-sided apertures'which are suiilciently accurate in formto merits.

My invention is based on the fact that certain fulfill all ordinaryrequirecycloids are generated around the perimeters of polygons havingrounded corners; hypocycloids are important in the development 01apertures which are multi-sided in section. The curves referred to areutilized in the following mariner:

While the cutting edge of my tool rotates once about the axis of thetoolholder, the latter also rotates several times in the. oppositedirection. I

about the axis of the multi-sidedaperture'being generated. Moreo'vertheratio of the speeds of rotation of the tool about these two axesdetermines the number of sides of the multi-sidedl Again to producemulti-sided' aperaperture. tures having flat sides the radial distanceof the cutting edge of the tool from its axis must be correctlyproportioned to the distance between the tool axis and the axis ofmulti-sided -aper-' ture.

It is an' object of the invention to provide a machine for generatingmulti-speed apertures all the lateral walls of which are of equal lengthand disposed at a common angle to one another and by which allmulti-sided apertures cut when the device has once been set areidentical. Moreover the machine may be so set that all, the'sides of themulti-sided aperture are flat.

Another object of theinvention is to provide a machine for generatingmulti-sided apertures which is simple in construction, has only fewmoving parts, requires very little attention when in ope tion, and whichdoes not-subject the cutting 01 to excessive wear.

A further object of the invention is to provide .a machine forgenerating multi-sided apertures wherein the tool spindle is rotatedthrough gearing, and wherein the spindle, which rotates at a constantspeed, is simultaneously rotated about a secondaxis in alignment withlongitudinal axis of the aperture beinggenerated.

Yet another object of the invention is to provide a machine for cuttingmulti-sided apertures wherein the ratio of the cooperating gears con-ZIP , lg-urel.

I Figure '1 is a longitudinal sectionshowlng one embodimentof-theinvention.

Figure 2 is a section on the line" IIII of somewhat imodifiedconstruction.

Figure 3. a 1 a Figure-'5 is a longitudinal section showing anothermodification. 1 I I Figure 6 i a section on VI--VI of Figure 5.

. Figure '7 is a'partial longitudinal section show-- ing a slightfurther modification. r s

Figure 8 is a longitudinal section showing an- 3 showsa longitudinalsection of a I Figure-4 is a section on the line IV- I V. cf

othenmodified form of the invention wherein" the axis of the toolspindle islinclined to the axis of the multi-sidedaperture to begenerated.

Figures 9 and 10 are'enlarged sectional details showing .methods ofadjustablymounting: the' tool for angular movement upon the toolspindle. J Referring first to Figures 1 and 2, the drive spindle orshaft I has a shank I mounted therein neath the spindle I and is"rotatably supported in a' fixed frame 3. The said. shank 2 isaisoprovided with-an eccentric tapered bore to re- 'ceive a cone 4. Fixedeccentrically-upon thev latter is a gear 5,'and'projecting from theopposite fac ofzthe said gear andconcentrictheretrols the number ofsides generated around the aperture; and wherein by varying the radiallength of projection of the cutting tool from the tool spindle axis thelength of the sides of the multi-sided aperture generated is changed.

Some of the preferred embodiments of the invention are hereinafter morefully described drawings in which:

with is a guide pin 6 which is rotatably mounted in a bearing I formedin a movable guide 8.

' for'rotation therewith. The shank! projects be- Mounted for rotationin the latter is a tool spindie I0 upon the upper extremity of which agear 9 is concentrically fixed which mesheswltl the gear 5. II denotesthe operating extremity of the tool spindle I0 which in the presentinstance is integral with th latter.- I2 is a tool bit carried by thespindle I0 and projecting. radially therefrom to cut the'lateral facesof an aperture It due to thefact that the axis C :of the gearS and itspin 6 is'spaced a distance r'irom the axis B I a of the drive spindle Irotation of the latter moves 4 the-guide 8 around an axis M whlchmustcoin- .cide with. the axis of the multi-sided'aperture- I515 begenerated. Moreover the axis M is parallel 2 to and spaced from the axisA of the tool spindle a distance 1' which isequal to the distance rbetween the axes B and C.

The circular pathof movement of the guide is insured by the carriage l4,movement of which 5 occurs simultaneously in two directions at rightangles to one another along the ways I'l and I8 and I9 caused by therotation of the eccentric pin 6. The distance r is regulated by therotary position of the cone 4 in the eccentric bore of the shank 2because the said cone is eccentric with the gear 5 and therefore may beturned so that its eccentric mounting in the shank 2 either through thegears-38 and 31. The axis M should complements or offsets theeccentricity of the gears 5-. The ratio of the teeth in the two gears 5and 9 controls the shape of the multi-sided apertures generated;. withthese gears proportioned 1:2 a triangular aperture. is obtained; andwhen proportioned 1:3 the aperture is made rectangular.

In the modification shown in Figures 3 and 4, 29 denotes portions of afixed frame in which the extremities of two 'spaced parallel columns 28are supported. Bushings 24 eccentrically bored at 2'! 'are mounted forrotation about columns 26 and have gears 25 fixed thereon. A guide 2|has a spindle 22 rotatably mounted therein, and fixed upon the latter isa gear 26 opposite sides of which mesh with the gears 25.

Integral with the guide 2| areopposed lateral extensions 23 throughwhich the bushings 24 extend and wherein they are rotatably mounted.

A universal joint 30 is secured both to the upper extremity of the toolspindle 22 and also to a drive spindle or shaft 3| which turns about afixed axis B The eccentricityof the tool spin-,- dle 22 relative to thedrive shaft 3|, which is represented by the distance r between the driveshaft axis B and the axis A of the tool spindle 22, must be equal to thedistance 3' between the axes D of the columns 28 and the axes E'of thebushings 24. It is therefore obvious that the rotation of the toolspindle 22 about its own axis A imparts rotation to the bushings 24through the gearing 26 and 25, and, due to the eccentric mounting of thesaidbushings upon the fixed columns 28, rotation is also imparted to theguide 2|, through which the vtool spindle 22 extends, about the saidaxis B -Obviously,

in this form of construction the guide 2|, the

bushings 24 and the gears 25 and 26 may all be moved axially togetherupon the columns 28 to provide axial feed for the tool spindle 22;moreover in this form of construction the axis B is in alignment withthe 'axis about which the guide 2| is rotated and must therefore be inalignment with the axis of the multi-sided aperture being generated. v

In Figures 5 and 6 the tool spindle 32 is eccentrically mounted in aguide 33, and in order to make the view shown in Figure 5 clearer thiseccentricity is perpendicular to the plane on which the section istaken. The guide 33 is concentrically supported in a stationary frame34- so that its axis is coaxial with th axis M of the latter. The guide33 is in the present instance rotated by means of a belt 35passingthrough a suitable opening .36 in the frame 34 and around theguide periphery though other means may coincide with the axis of themulti-sided aperture to be generated. In this case the cross sectionalform of the aperture is dependent upon the total ratio of the. twocoacting pairs of gears. For instance, a 3:2 ratio produces a triangularhole, and a 4:3 ratio produces a rectangular hole.

Figure 7 shows a slight modification of the construction just describedand illustrates one means for varying the distance 1 between the axis Mand A, and thus the. diameter of the circular path around which the axisof the tool spindle travels as it rotates about its own axis. The boreof the guide 33a is longitudinally inclined and a-bushing 54, theperiphery of which is correspondingly inclined, is longitudinallymovable therein, so that the bore of the bushing is parallel with theaxis M and eccentric with theperiphery of the guide 3311. Obviously, byadjusting the longitudinal position of the bushing in its guide in thedirection of the arrows X or Y the distance 1 may be varied.

However in order to make this arrangement operative in the constructionshown in Figures 5 and 6 the gears 31 and 33 must b changed and anotherset of larger or smaller diameter used for each vertical setting of thebushing 54, which must therefore be at certain predetermined ver- 5tical positions so that the set of gears 31 and 38 employed meshproperly with one another. Similarly such an adjustment may also beemployed in the arrangement shown in Figures 3 'and '4 by changing thegears 25 and 26 for others 0 of larger or smaller diameter.

Figure 8 shows an inclined tool spindle 43 having a bevel gear 44 fixedupon its upper extremity which travels around an internal gear 46provided within a stationary housing 45. The axis A of the spindle isinclined at an angle a to the axis M of the frame and intersects thelatter at the point K below the said frame. The tool spindle 43 is inits inclined position eccentrically mounted in a guide 41 which iscoaxial with the internal gear 46 insomuch that the axis A intersectsthe'bushing axis M at K beneath the bottom of the said guide. The guide41 is connected to a drive spindle or shaft 48 which be employed forturning said guide. Fixedupon 7 the spindle 32 is a gear 31 which mesheswith a gear 38 upon a stub shaft 33 supported in a laterally projectingmember 46 integral with the said guide 33. Fixed upon the shaft 39 is asecis mounted for rotation in the 'upper portion of the housing 45 andextends therethrough in alignment with the axis M.

When the shaft" and the guide 41 are turned the bevel gear 44 travelsaround the internal gear 46 and the tool spindle 43 is rotated aboutboth axes A and M. The proportionate sizes of the gears 44 and 46control the cross-sectional form of the multi-sided apertures generatedby the cutting edge S of the tool 49. For instance, if the ratio of thegears is 3:2 a triangular hole is formed and if the ratio is 4:3 the holgenerated is rectangular. From the foregoing, it will be clearly seenthat the tool spindle 43 turns both about its axis A and about the axisW of the guide 41. Moreover on account of the inclination of these twoaxes to one another, the

transverse distance between them varies accord-.

section K. ond gear 4| which engages a gear 42 concentri- The cuttingedge S of the tool must be sufwith the internal gear through which saidspindle is turned by the rotation of the guide, and a tool carried bythe spindle, said tool having a Figure 9 is an enlarged diagrammaticview showing a modification of the structure shown in Figure 8 whereinthe tool spindle 43a is tubular and the point K is located beneath thecut-- ting edge S of the tool 49. Axially movable in the spindle 43a isa rod 52 having a laterally disposed pin 60 projecting therefrom. Formedin the tool spindle 43a is an inclined guide 6| in which a toolholder 50is slidably mounted. The outer extremity of the pin 60 is a sliding fitin an aperture 50a in the toolholder 50 so that it may slidetherethrough as the rod 52 is moved in the tool spindle 43a and the saidtoolholder is correspondingly moved in the guide 6|. construction it isobvious that upon feeding the rod 52 in the guide 43a the cutting edge Sof the tool 49 must travel along a line S'-K parallel with the base ofthe guide 6| that is at an angle 3 to the axis A of the tool spindle;and a tie-'- notes the angle between the axes A and M The arrangementshown in Figure 10 is practically identical to that shown in Figure 9except that the point K, which again designates the intersection of theaxes A and M is located above instead of beneath the tool 49, andtherefore the line S-K lies above instead of beneath the said tool. Therod 53 and the-tool holder and the pin 60a correspond to the rod 52, thetoolholder 50 and the pin 60 above described. a again denotes the anglebetween the cutting edge spaced axially from the point ofintersectionand displaced laterally from the axis of the spindle.

2. A machine for generating multi-sided apertures comprising a frame, adrive shaft mounted for rotation therein, a guide fixed on the shaft forrotation in the frame, an internal bevel gear on the frame, a spindlemounted for rotation in the guide at an inclination to the guide axis,said guide and spindle axes being adapted to inter sect, a bevel gearfixed on the spindle and meshing with the internal bevelgear whereby thespindle is turned by the rotation of the guide,

Inthis' and a tool carried by the spindle, .said tool having a cuttingedge spaced axially from the point of intersection and displacedlaterally from the axis of said spindle.

ported by said spindle, said tool including a cutting edge displacedlaterally from the rotative axis of the spindle, means for rotating saidguide, I

and cooperating means on said frame and spindle whereby rotation of theguide causes rotation of the'spindle about its rotative axis to therebyimpart to the cutting edge of the tool a axes A and. M and B the anglebetween the line S-K and the axis A The purpose of the embodiments shownin Figures 9 and 10 is to provide means, by feeding the rod 52 or 53inthe spindle 43a, for forming multi-sided apertures the walls of whichare all uniformly inclined to the longitudinal axis M and the latter ofcourse also coincides with. the

' axis of the multi-sided aperture being generated. In other words theapertures thus formed are of different sizes at the top and bottom, thushaving the shape of a truncated pyramid.

It will of course be noted from the drawings that as above stated thetool spindle rotates about its own axis in the opposite direction tothat in which it travels around the second axis.

a spindle mounted for rotation in the guide about its axis, saidaxisbeing angularly disposed withv reference to the guide axis and adaptedto intersect the same, a gear on the spindle meshing hypocycloidalmovement with reference to a circular line'about the rotative axis ofthe guide.

4. Mechanism of the class described comprising a frame, saidframeincluding a circular portion having a driving surface around itsinternal periphery, a guide rotatable in the frame, a tool spindlerotatable in the guide with its axis of rotation eccentrically disposedwith relation to the rotative axis of the guide, said spindle includinga circular portion having a driven surface around its external peripheryin operative engagement with the driving surface in said frame, means,for producing relative rotation of said frame and-guide, and a cuttingtool positioned by said spindle.

5. Mechanism of the class described comprising a frame, said frameincluding a circular porguide, and a cutting tool positioned by saidspindle.

6. The mechanism set forth in claim 5 wherein the cutting edge of thetool is laterally displaced from the spindle axis and axially displacedfrom the intersection of the guide and spindle axes of rotation.

,l-IANS JOACHIM scnaonna.

